Investigators retrieve the helmet of Fire Capt. Michael Bell from the rubble at 313 Farmington Falls Road in Farmington on Tuesday and present it to a waiting firefighter. Bell, 68, was killed in Monday's propane explosion at the LEAP building.

Maine State Police lead a procession honoring Farmington firefighter Michael Bell as the motorcade passes through the University of Maine at Farmington campus Tuesday. Bell was killed in a building explosion Monday. Students reported being awakened by the sound of the explosion. Morning classes at the university were canceled.

A police officer salutes as the procession carrying Farmington firefighter Michael Bell arrives in Farmington on Tuesday. Bell was killed in a building explosion Monday.

University of Maine students react as the procession honoring Farmington firefighter Michael Bell passes through campus Tuesday. Bell was killed in a building explosion Monday. Students reported being awakened by the sound of the explosion. Morning classes at the university were canceled in the wake of the tragedy.

Farmington firefighters ceremoniously carry the helmet of Fire Capt. Michael Bell, draped in a cloth, after retrieving it from the rubble at 313 Farmington Falls Road in Farmington on Tuesday. Bell, 68, was killed in Monday's propane explosion at the LEAP building.

Firefighters embrace after investigators retrieved the helmet of Fire Capt. Michael Bell from the rubble at 313 Farmington Falls Road in Farmington on Tuesday. Bell, 68, was killed in Monday's propane explosion at the LEAP building.

Larry Johnson, 84, and his wife, Maxine, 82, lower the flag at Norridgewock, Maine Baptist Church to half staff in tribute to Farmington firefighter Michael Bell. Bell was killed in a building explosion in Farmington on Monday. Maxine said the flag would remain at half staff until sundown Thursday.

Fire engines escort Tuesday, September 17, 2019, the remains of Farmington Fire Rescue Captain Michael Bell from Augusta to Farmington. Bell was killed in an explosion Monday that also injured six other firefighters and a maintenance worker at the LEAP building in Farmington.

State Police and Department of Corrections canine handlers salute Tuesday, September 17, 2019, the remains of Farmington Fire Rescue Captain Michael Bell during an escort through Augusta to Farmington. Bell was killed in an explosion Monday that also injured six other firefighters and a maintenance worker at the LEAP building in Farmington.

People gather at the site of an explosion that claimed the life of Capt. Michael Bell, 68, a 30-year member of the Farmington Fire Rescue Department and brother of the department’s chief at 313 Farmington Falls Road in Farmington late Monday night, September. 17, 2019.

Officials with the Maine State Police and Franklin County Sheriffs Department stand in the middle of US Route 2 in Farmington late Monday night, September. 17, 2019 at the scene of a deadly explosion that claimed the life of one firefighter and injuring several others.

A deputy with Franklin County Sheriff's Office walks through the debris field of an explosion at 313 Farmington Falls Rd in Farmington late Monday night, September. 17, 2019.

A trooper with Maine State Police stands in the debris field of an explosion at 313 Farmington Falls Road in Farmington late Monday night, September. 17, 2019.

Officials with the Maine State Police and Franklin County Sheriffs Department stand in the middle of US Route 2 in Farmington late Monday night, September. 17, 2019 at the scene of a deadly explosion that claimed the life of one firefighter and injured several others.

Dozens attended the prayer service held Monday at St. Joseph Catholic Church in Farmington following an explosion that claimed the life of one firefighter and injured several others.

A prayer service was held Monday night at St. Joseph Catholic Church in Farmington for those affected by an explosion earlier in the day. An unidentified firefighter and Livermore Fire Chief Donald Castonguay were among those attending.

An explosion at 313 Farmington Falls Road claimed the life of a Farmington firefighter and injured seven others Monday. A candlelight vigil was held at Old South Congregational Church that evening. Pictured in front are Reverend Sara Bartlett of Auburn at left and Rev. Margaret Proctor of Wilton.

An investigator walks through debris as multiple local, state and federal agencies investigate the deadly explosion at 313 Farmington Falls Road in Farmington on Tuesday.

A Farmington firefighter and police officer inspect the site of the LEAP building explosion on Tuesday.

Firefighters from the Farmington Fire Department arrive at the scene of a deadly explosion to retrieve the helmet of a fellow firefighter at 313 Farmington Falls Road in Farmington on Tuesday.

Investigators from local, state and federal agencies scour the debris as they investigate a deadly explosion at 313 Farmington Falls Road in Farmington on Tuesday.

Investigators from local, state and federal agencies scour the debris as they investigate a deadly explosion at 313 Farmington Falls Road in Farmington on Tuesday that killed one firefighter on Monday.

An investigator clears the scene of medical equipment as multiple local, state and federal agencies investigate the deadly explosion at 313 Farmington Falls Road in Farmington on Tuesday.

A deputy with Franklin County Sheriff's Office walks through the debris field of an explosion at 313 Farmington Falls Road in Farmington late Monday night, September. 17, 2019.

An investigator pulls belongings from the debris at 313 Farmington Falls Road in Farmington on Tuesday.

A firefighter watches as investigators retrieve the helmet of Fire Capt. Michael Bell from the rubble at 313 Farmington Falls Road in Farmington on Tuesday. Bell, 68, was killed in Monday's propane explosion at the LEAP building.

Investigators retrieve the helmet of Fire Capt. Michael Bell from the rubble at 313 Farmington Falls Road in Farmington on Tuesday. Bell, 68, was killed in Monday's propane explosion at the LEAP building.